1. Field of the Invention
The present invention relates to mechanical devices and, more particularly, to a method and apparatus for determining warranty periods for mechanical devices.
2. Description of the Related Art
Most mechanical systems, including mechanical presses, have a certain operational lifetime based upon their construction material, their structure, and general dynamic and static loads placed thereon. Manufacturers warrant their products for a particular length of time based upon certain assumptions of customer use and abuse of the apparatus and time of operation.
Currently, the warranty period for a mechanical device, such as a mechanical press, is based upon inaccuracies, such as predicted use conditions and run time. These current methods of determining warranty do not account for certain usage which may adversely effect the mechanical device more quickly than other less abusive usage, nor do they account for time of use which is greater than or less than the predicted amount. For this reason, a mechanical device owner does not have an accurate way to predict the impact of a particular application of the mechanical device. Also, manufacturers do not have accurate means to measure the impact of device application so that they may suggest that the owner take reasonable maintenance procedures to keep the device in good operating condition, offer extended warranties, or offer an automatic buyback program.
Operating mechanical devices, for example, mechanical presses, at particular speed, force, or load levels may have a greater impact on the longevity of the mechanical device. In these cases, the impact on the device may be amplified in such a way that the magnitude of the force or load is not an accurate indicator of the effect of these applications on the longevity of the mechanical device.
What is needed in the art is a way to monitor production operation conditions in a secure and confirmed way so that warranty periods for a particular mechanical device, for example, a mechanical press, may be accurately determined and offers of extended warranties or automatic buyback programs may be offered without risk to the manufacturer. Known problems with load sensors and other ways of accumulating load data on mechanisms include the fact that customers sometimes disengage such-load accumulators and/or counters and thereby undercount or underaccumulate the total use or force applied against the machine.
What is additionally needed in the art is a way to accurately determine the original warranty and actual production use of a mechanical device. Extended warranty could then be accurately determined at the conclusion of the original warranty by subtracting the actual production use from the original warranty. This calculation of extended warranty could be used in many ways, such as automatically offering the purchaser an extended warranty or offering an automatic buyback program.
What is further needed in the art is a system to monitor the actual production use of a machine to assist the customer in keeping particular machine applications within an identified limit.
The present invention is directed to improve upon the ability to accurately generate a measure of warranty for a mechanical device (e.g. a mechanical press) and to provide a method and apparatus for generating a measure of actual production use of the mechanical device so that an extended warranty may be accurately determined, or a substantially risk-free buyback program may be implemented.
The present invention provides a method and apparatus for determining the original warranty and extended warranty of a mechanical device, which includes developing an indicator of use severity that provides an accurate indicator of the impact of different applications on the longevity of the mechanical device.
The invention, in one form thereof, comprises a method of generating of measure of warranty for a mechanical device. The first step of this method is to develop an indicator of use severity for the mechanical device. Use severity is a quantity which relatively indicates how a particular use of a mechanical device impacts the longevity of the mechanical device. A high value of use severity is indicative of an application of the mechanical device which has a greater impact on the longevity of the mechanical device, whereas a low value of use severity would indicate an operation of a mechanical device which would less severely impact the longevity of the mechanical device. The next step of this method is to determine the maximum recommended use severity level. The maximum recommended use severity level is a use severity level beyond which the mechanical device should not be operated. This method further includes the steps of: determining the hours of operation for the original warranty period, providing a computational device and computing the original warranty use severity life for the mechanical device based upon the maximum recommended use severity level and hours of operation for the original warranty period. The maximum recommended use severity level is multiplied by the hours of operation to determine the original warranty period.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical device. In this form, this method includes the steps of: generating a cumulative measure of actual production use severity of the mechanical device for the original warranty period and computing the extended warranty use severity life remaining at the conclusion of the original warranty period for the mechanical device based upon the original warranty use severity life and the cumulative measure of actual production use severity. Extended warranty use severity life is a cumulative measure of use severity which remains at the conclusion of an original warranty and is computed by subtracting the actual production use severity from the original warranty use severity life.
The invention, in another form thereof, comprises a method of generating a cumulative measure of the actual production use severity of the mechanical device. This method includes the steps of: determining a count quantity for the mechanical device, monitoring the actual production use severity of the mechanical device, monitoring the count quantity of the mechanical device, tabulating actual production use severity versus count quantity, and computing a cumulative actual production use severity value for the original warranty period based upon the tabulated use severity versus count quantity values. Tabulated use severity versus count quantity values are summed over count quantity to produce a cumulative measure of the actual production use severity of the mechanical device which has units of (use severity xe2x80xa2count quantity).
The invention, in another form thereof, comprises a method of generating a measure of the extended warranty for a mechanical device. In one form, this method comprises the steps of: computing the average actual production use severity for the original warranty period and computing the extended warranty period based upon the extended warranty use severity life remaining at the conclusion of the original warranty period for the mechanical device and the average actual production use severity for the original warranty period. Extended warranty use severity life remaining at the conclusion of the original warranty is divided by the average actual production use severity for the original warranty period to determine the extended warranty period. In another form of the current invention, this method comprises the steps of: computing actual production use severity over discrete time intervals of equal length based upon the average actual production use severity measured over the discrete time interval and the length of the time interval, computing the extended warranty remaining at the conclusion of the first discrete time interval based upon the extended warranty use severity life and the actual production use severity for the first discrete time interval, and computing the extended warranty remaining at the conclusion of each discrete time interval based upon the previously determined extended warranty remaining at the conclusion of the previous discrete time interval and the use severity of each discrete time interval. In this way, extended warranty is continuously computed.
The invention, in another form thereof, comprises a method for calculating a measure of the extended warranty of a mechanical device which includes setting the measure of the extended warranty to zero if the monitored use severity of the mechanical device exceeds the maximum recommended use severity level.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical device which comprises the steps of: calculating a measure of the extended warranty and offering an automatic buyback of the mechanical device if the measure of the extended warranty is above a predetermined measure.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press. This method includes the steps of: determining the maximum recommended vibration severity level, determining the hours of operation for the original warranty period, providing a computational device, and computing the original warranty vibration severity life based upon the maximum recommended vibration severity level and hours of operation for the original warranty period. In this way, the maximum recommended vibration severity level is multiplied by the hours of operation for the original warranty period to compute a measure of the original warranty vibration severity life.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press. This method includes the steps of: generating a cumulative measure of the actual production vibration severity use of the mechanical press for the original warranty period and computing the extended warranty vibration severity life remaining at the conclusion of the original warranty period for the mechanical press based upon the original warranty vibration severity life and the cumulative measure of actual production vibration severity. In this way, the cumulative measure of actual production vibration severity is subtracted from the original warranty vibration severity life to compute a value of the extended warranty vibration severity life.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press which includes the step of: generating a cumulative measure of the actual production vibration severity use of the mechanical press. In this form, the step of generating cumulative measure of the actual production vibration severity use of the mechanical press includes the steps of: determining a count quantity for the mechanical press, monitoring the actual production vibration severity of the mechanical press, monitoring the count quantity of the press, tabulating actual production vibration severity versus count quantity, and computing a cumulative actual production vibration severity value for the original warranty period based upon the tabulated vibration severity versus count quantity values. In this way, the tabulated vibration severity values are summed over count quantity to achieve a value of cumulative actual production vibration severity which has units of (use severity xe2x80xa2count quantity).
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press. This method involves the use of vibration severity in determining the original warranty, actual production use, and the extended warranty. In one form, this method includes the step of: providing a sensor security device for verifying that the sensed vibration severity level is valid for the press.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press. This method includes the step of: generating a cumulative measure of the actual production vibration severity use of a mechanical press. In this form, this step includes: setting run time as the count quantity for the mechanical press, monitoring the actual production vibration severity of the mechanical press, monitoring the run time of the press, tabulating actual production vibration severity versus run time, computing a cumulative actual production vibration severity value for the original warranty period based upon the tabulated vibration severity versus run time values, and providing a crank shaft sensor for detecting the crankshaft rpm of the press so that it may be compared with the sensed run time and vibration severity to provide a backup check to ensure that the devices which monitor the vibration severity and run time of the press have not been altered or disconnected.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press which includes the steps of: providing a computational device and providing a tamper proof enclosure for the computational device.
The invention, in another form thereof, includes the step of generating a cumulative measure of the actual production vibration severity use of a mechanical press. In one form, this step comprises: generating a unique press vibration severity/reliability zone chart, generating vibration severity zone life acceleration factors corresponding to the zones of the vibration severity/reliability zone chart, comparing the monitored actual production vibration severity to the vibration severity/reliability zone chart to determine in which reliability zone the press is operating, associating the monitored actual production vibration severity with the appropriate zone life acceleration factor, computing a weighted actual production vibration severity value using the monitored actual production vibration severity and the appropriate vibration severity zone life acceleration factor, recording weighted actual production vibration severity values vs. time, and computing a cumulative actual production vibration severity value using the weighted actual production vibration severity values vs. time. In this way, recorded weighted actual production vibration severity values versus time are summed over count quantity to compute a cumulative value of actual production vibration severity which has units of (vibration severity xe2x80xa2time).
The invention, in another form thereof, includes the step of generating a unique press vibration severity/reliability zone chart. This step includes: running a press through a plurality of continuously recurring cycles; monitoring and recording the speed of the press, monitoring and recording the load exerted by the press; monitoring and recording vibration severity magnitude velocity induced in the press utilizing a vibration sensor, for example, an accelerometer means attached to the press; plotting the recorded vibration severity magnitude on a load vs. speed graph; varying the speed and the load of the press and repeating the previous steps until a plurality of vibration magnitudes are recorded; and defining curves of equal vibration severity magnitudes on the graph to divide the graph into a plurality of zones representing different vibration magnitudes.
The invention, in another form thereof, comprises a method of generating a measure of warranty for a mechanical press which includes the step of calculating a measure of the extended warranty. In one form, this step includes: computing the average weighted actual production vibration severity for the original warranty period and computing the extended warranty period based upon the extended warranty vibration severity life remaining at the conclusion of the original warranty period for the mechanical press and the average weighted actual production vibration severity for the original warranty period. In another form, this step includes: computing vibration severity use over discrete time intervals of equal length based upon the average actual production vibration severity measured over the discrete time interval and the length of the time interval, computing the extended warranty remaining at the conclusion of the first discrete time interval based upon the extended warranty vibration severity life and the actual production vibration severity use for the first discrete time interval, and computing the extended warranty remaining at the conclusion of each discrete time interval based upon the previously determined extended warranty remaining at the conclusion of the previous discrete time interval and the vibration severity use for each discrete time interval. In this way, extended warranty is continuously computed.
The invention, in another form thereof, comprises a method for calculating a measure of the extended warranty of a mechanical press which includes setting the measure of the extended warranty to zero if the monitored vibration severity of the mechanical press exceeds the maximum recommended vibration severity level.
The invention, in another form thereof, includes a counter for sensing a count quantity for the press. The counter can be, for example, a run time sensor which senses whether the press is operating. The invention further includes a vibration sensor, for example, an accelerometer for sensing vibration severity of the press. The vibration sensor is attached to the press. A vibration severity life monitor, for example, a microprocessor is communicatively connected to the counter and the vibration sensor. The vibration severity life monitor tabulates sensed information such as, count quantity and vibration severity. The vibration severity life monitor stores an original warranty value and computes a value of extended warranty based upon the original warranty and the tabulated and stored information.
The invention, in another form thereof, includes a vibration sensor and a vibration severity life monitor. A sensor security device is communicatively connected to both the vibration sensor and the vibration severity life monitor. The sensor security device receives the vibration severity value from the vibration sensor and determines whether the sensed vibration severity level is within an acceptable range for the press being monitored.
The invention, in another form thereof, includes a zone factor device which is, for example, a microprocessor. The zone factor device stores a vibration severity zone chart for the press being monitored as well as a plurality of zone life acceleration factors which correspond to the vibration severity zones on the vibration severity zone chart. The zone factor device receives sensed vibration values and communicates these sensed vibration values along with corresponding vibration severity zone chart information to the vibration severity life monitor.
The invention, in another form thereof, includes a crankshaft sensor which detects a crankshaft rpm value for the press. A display device displays information that is tabulated and computed in the vibration severity life monitor. The display device is communicatively connected to the vibration severity life monitor.
The invention, in another form thereof, includes a first tamper proof housing which surrounds the vibration severity life monitor and a second tamper proof housing which surrounds the sensor security device.
An advantage of the present invention is that it permits summation or accumulation of vibration severity level data over the actual life time of use of the mechanical press thereby forming a record of such use. When such use of mechanical presses can be determined under such confirmed, controlled conditions, it may be possible to accurately compute an extended warranty or offer a substantially risk-free buyback.
Another advantage of the present invention is that operating conditions which have a greater impact on the longevity of the mechanical device are weighted accordingly to determine accurate measures of warranty.
A further advantage of the present invention is that such use of an accumulating vibration severity or use severity monitor may confirm that vibration severity or use severity has been under control at all times, which will increase the salability of the press.
A further advantage of the invention is that by accumulating and displaying the total vibration severity or use severity applied against the mechanical press, preventive maintenance and other replacement operations may be done prior to actual failure or reduction in utility of particular components of the press, thereby reducing overall maintenance costs.
Yet another advantage of the present invention is that it creates a documented record of the complete operational history of the press which enhances the customer""s resale payback, if they would ever wish to resell the press. Presses would have higher resale values if an accurate measure of past press use could be communicated to a potential purchaser.
Yet another advantage of the invention is that an automatic buyback built/re-builder could be possible for the press if at any time during the press life vibration severity application could be confirmed. Based upon known historical trends of vibration severity analysis, it would be possible to determine how much xe2x80x9coperational lifexe2x80x9d the press maintains prior to any necessary rebuild or overhaul maintenance.